P0812
DTC P0812: Open in Transmission Range Switch ATP R Switch CircuitNOTE:
^ Before you troubleshoot, record all freeze data and any on-board snapshot, and review General Troubleshooting Information.
^ This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.
1. Turn the ignition switch ON (II).
2. Shift to the R position, and verify the A/T R SWITCH signal with the HDS in the A/T data list.
Is the A/T R SWITCH ON?
YES - Intermittent failure, the system is OK at this time.
NO - Go to step 3.
3. Turn the ignition switch OFF.
4. Disconnect the transmission range switch connector.
5. Check for continuity between transmission range switch connector terminal No. 10 and body ground.
Is there continuity?
YES - Go to step 6.
NO - Repair open in the wire between transmission range switch connector terminal No. 10 and ground (G101), or repair poor ground (G101), then go to step 9.
6. Turn the ignition switch ON (II).
7. Measure voltage between transmission range switch connector terminals No. 7 and No. 10.
Is there battery voltage?
YES - Go to step 8.
NO - Repair open in the wire between PCM connector terminal B14 and the transmission range switch, then go to step 9.
8. Check for continuity between transmission range switch connector terminals No. 7 and No. 10 while the shift lever is in the R position, and when the shift lever is shifted to any position other than R.
Is there continuity while the shift lever is in the R position, and no continuity when the shift lever is shifted to any position other than R?
YES - Check for loose or poor connections at PCM connector terminal B14. If the connection is OK, update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck for DTC P0812. If the symptom/indication goes away with a known-good PCM, replace the original PCM, then go to step 9.
NO - Replace the transmission range switch, then go to step 9.
9. Clear the DTC with the HDS.
10. Test-drive the vehicle in the R position at speeds below 3 mph (5 km/h) for more than 2 seconds, then increase the speed and test-drive at speeds over 3 mph (5 km/h) for more than 2 seconds. Slow down and stop the wheels.
11. Monitor the OBD status for P0812 in the DTCs/Freeze Data in A/T Mode Menu for a pass/fail.
Does the result indicate PASSED?
YES - Troubleshooting is complete.
NO - If the PCM was updated and the screen indicates FAILED, substitute a known-good PCM, then return to step 9. If the PCM was substituted and the screen indicates FAILED, return to step 1 and recheck. If the screen indicates NOT COMPLETED, return to step 10.